The present invention relates to a disposable antibacterial filter device particularly applicable to lines for connection to spirometric devices.
As it is known, spirometric devices are frequently used in respiratory physiopathology and bronchopneumology wards and in sports medicine centers.
The spirometric technique is used to determine the volume of the inspired air or to study the composition of the expired air in order to ascertain the functionality of the lungs and of the basal metabolism.
The patient undergoing a spirometric test must breathe into the spirometer through a plastic hose which is provided with a mouth-nose mask or with a mouthpiece that allows to convey the air to the device.
Since most of the patients undergoing this test may be affected by respiratory disorders, there is the problem that the viral and bacterial loads present in the air expired by a patient during the spirometric test are carried through the hose to the device, which is thereby contaminated.
The bacterial contamination of the spirometer and of the hose may therefore be transmitted to the patients that are subsequently subjected to the same test.
In order to prevent any possibility of contamination of the device and of the hose as well as any cross-contamination, antibacterial filters interposed between the hose and the mask or mouthpiece have already been used.
The filter must have an extremely low flow resistance to avoid altering the respiratory parameters recorded during the spirometric test and must also have a good bacterial retention ability.
The filters currently in use comprise a box-like container inside which there is an antibacterial filtration membrane which is pleated and arranged in a pack-like configuration.
First of all, with this arrangement the filtration surface is considerably limited, so that antibacterial effectiveness may be severely compromised.
Another drawback resides in the fact that these kinds of filters have a very high cost and their disposable use is consequently particularly expensive.
Furthermore it is necessary to replace, beyond the filter body, the mouthpiece or mask which is in contact with the user.